i have a script used in my application to communicate with the application on a board and cater its requests over ethernet.
my script acts as client program, the link establishing code is as follows

sub tb_data_lnk_open 
{ 
my ($link_add); 
my ($network_addr, $port_addr); 
my ($remote_host, $remote_port); 

$link_add = $_[0]; 

#=====================================================================
+====# 
# The input $link_add contains the IP address and port in a single # 
# separated by a - # 
#=====================================================================
+====# 
($remote_host, $remote_port) = split( /-/, $link_add); 

#=====================================================================
+====# 
# Create a socket. The socket is openend with TCP properties # 
#=====================================================================
+====# 
socket(LINK_HNDL, PF_INET, SOCK_STREAM, getprotobyname('tcp')); 

#=====================================================================
+====# 
# Remote address to connect in the network format # 
#=====================================================================
+====# 
$network_addr = inet_aton($remote_host) 
or return 0; 

$port_addr = sockaddr_in($remote_port, $network_addr); 

#=====================================================================
+====# 
# Connect to the server which is already listening # 
#=====================================================================
+====# 
connect(LINK_HNDL, $port_addr) 
or return 1; 

return 0; 
}
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and recieve function is as follows, which i want it to timeout after 100 seconds

sub tb_data_recv 
{ 
my ($size, $data, $temp, $length_read); 
$size = $_[0]; 
$data = ""; 
$length_read = length($data); 

my $time_elapsed = 0; 
my $start_time = time(); 
#print "\nStart Time :$start_time "; 
my $count = 0; 
while($length_read < $size) 
{ 

recv(LINK_HNDL, $temp, $size - length($data), $flags); 

$time_elapsed = time() - $start_time; 
#print "\n$count|Time Elapsed :$time_elapsed : $TIME_OUT : **$temp** :
+ **$data** \n"; 
if($time_elapsed > $TIME_OUT) 
{ 
$data = ""; 
goto TEST_DOC_REP_CRASH; 
#return $data; 
} 

$data = $data.$temp; 
$length_read = length($data); 
$count++; 
} 

# print "\nTimeOut Not Detected"; 
return $data; 
}
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but if i switch of board, where server is running, the perl script is still blocked at recv call.
can any one please tell me how to achieve that.(i have tried few things i found on internet, like setting timeout "setsockopt(LINK_HNDL, SOL_SOCKET, SO_RCVTIMEO, pack('LL', 1, 0));")
but still didn't work.
Script runs on windows machine, server/application(c code) runs on board on montavista linux.
if this is not the right place to ask, please give me pointers to where should i ask.
If anyother information is needed for understanding or solving, do tell me.